The knitting of fabrics on warp knitting machines is known in the prior art. Warp knitting machines generally have one or more warp beams which supply the threads to be knitted. The threads are separated on a sley or thread separator mechanism. The threads thereafter pass over a tensioning bar and pass to a knitting mechanism. The knitting mechanism thereafter knits the individual threads into a knitted fabric wherein each vertical row of stitches is called a wale and each horizontal row of stitches is called a course. One conventional warp knitting machine is produced by the Textile Machine Works of Reading, Pennsylvania.
The production of a patterned effect on fabric knitted by a warp knitting machine is also known in the prior art. Prior apparatus and methods of producing such a patterned effect have generally been complex and have necessitated slowing down the operating speed of the knitting machine. The output of the knitting machine is thus reduced.
One type of prior art device for producing a patterned effect on knitted fabrics is known as a "Swan warp attachment". This type of attachment is a complex mechanism which utilizes a plurality of individual droppers or tensioning mechanism to produce the patterned effect.